Synthetic fibers and fabrics having microbicidal activity



nited States Patent 3,034,957 SYNTHETIC FIBERS AND FABRICS HAVINGMICROBICIDAL ACTIVITY James L. Smith and Robert C. Harrington, Jr.,Kingsport,

Tenn, assignors to Eastman Kodak Company, Rochester, N.Y., a corporationof New Jersey No Drawing. Filed July 2, 1958, Ser. No. 746,076 Claims.((31. 167-385) This invention relates to improved fibers and fabrics,and more particularly, to synthetic fibers and fabrics of celluloseacetate, resins comprising copolymers of vinylidene chloride withacrylonitrile, and polyesters of 1,4- cyclohexanedimethanol andterephthalic acid having microbicidal activity.

For many years, attempts have been made to produce fibers and fabricswhich would effectively retard the growth of various microorganisms.Generally, this purpose has been accomplished by a separate treatment inwhich the fabric is coated with a resinous material containing amicrobicide. Such a treatment has proved to be relatively ineffectivebecause the resin coating would tend to flake off in normal use, and theusual washing or laundering operation would very quickly destroywhatever microbicidal properties that might be present. In addition,resinous coatings tend to change the hand of fabrics in an undesirablemanner. Other treatments have consisted of treating the fabric in asolution of a microbicide. Fabrics containing some of these microbicidalagents are claimed to be substantive, but the microbicidal agents areactually held so loosely that they can be easily laundered out. Hence,it is desirable to have synthetic fibers and fabrics that havepermanence of microbicidal activity, this result being obtained withoutaffecting the appearance and physical properties thereof.

Also, any microbicidal additive to a fiber or fabric for clothing use,while it must be sufiicient to kill or inhibit the growth ofmicroorganisms, it must not be toxic or poisonous to the wearer of theclothing. In addition, any additive to a synthetic textile fiber must becompatible with the particular synthetic resin, have no adverse effectson dyeing characteristics and create no difficulty in the spinningthereof, many eifective microbicides for a wide variety of substratesfailing to meet these and the other above-described requirements insynthetic fibers and fabrics.

It is an object of this invention to provide novel synthetic fibers andfabrics having improved microbiological growth inhibition.

It is another object of this invention to provide novel synthetic fibersand fabrics capable of retaining microbiological growth inhibitionproperties after repeated washings or launderings, dry cleanings andwearings.

it is another object of this invention to provide novel synthetic fibersand fabrics having microbicidal activity which are not significantlydifferent from corresponding fibers and fabrics without such activitywith respect to hand, dyeability, appearance, and the like.

It is another object of this invention to provide novel synthetic fibersand fabrics capable of inhibiting microbiological growth and which areamenable to the various phases of fiber and fabric processing withoutloss of this inhibitory power.

it is still another object of this invention to provide novel syntheticfibers or fabrics prepared therefrom which will resist the formation ofobnoxious odors after having become contaminated by perspiration or likesoiling agents.

it is likewise an object of this invention to provide novel sanitarysynthetic fibers or fabrics prepared therefrom such that microbiologicalcontamination spread from one wearer to another or from one place on awearers body to another would be significantly reduced or eliminated.

It is also an object of this invention to provide novel fibers andfabrics of cellulose acetate, resins comprising copolymers of vinylidenechloride and acrylonitrile, and polyesters of l,4-cyclohexanedimethanoland terephthalic acid having microbicidal activity.

These and other objects are attained by means of this invention asdescribed hereinafter with reference to preferred embodiments thereof.

We have found that relatively low concentrations of 3,4,4-trichlorocarbanilide can be incorporated into a solution or melt of celluloseacetate, resins comprising copolymers of vinylidene chloride andacrylonitrile or polyesters of l,4-cyclohexanedimethanol andterephthalic acid, and spun, extruded or drawn into fibers byconventionalmethods to produce improved fibers having microbicidalactivity. By incorporating 3,4,4-trichlorocarbanilide into the liquidresin prior to spinning, a fiber results which has the3,4,4'-.trichlorocarbanilide substantially uniformly distributedtherein. Thus, fabrics prepared from such fibers have the 3,4,4-trichlorocarbanilide microbicide built in or locked in. Thus, thesynthetic fibers and fabrics of the invention are quite unlike naturaland synthetic fibers and fabrics which have been superficiallysurface'treated with various agents. The microbicide in the syntheticfibers and fabrics of the invention is available to render itsmicrobicidal effect and yet can not be completely removed by repeatedwashings, dry cleanings and abrasions, such properties not beingpossessed by conventional surface treated fibers and fabrics.

The resins or plastic compositions comprising the fibers or fabrics ofthe invention are cellulose acetate, resins comprising copolymers ofvinylidene chloride and acrylonitrile, and polyesters of1,4-cyclohexanedimethanol and .terephthalic acid. Polyesters of1,4-cyclohexanedimeth anol and terephthalic acid, and their method ofpreparation, are described in the copending application, Ki'bler et al.,US. Serial No. 554,639, filed December 22, 1955, now US. Patent No.2,901,466. Cellulose acetate is a wellknown resin and can be preparedand spun into fibers by such methods as are disclosed in Stone US.Patent No. 2,000,047 and Stone US. Patent No. 2,000,- 048. Celluloseacetates having acetyl contents of about 38% to 45% by weight aresuitable, with acetyl contents of about 38% to 41% being preferred.Fiber-forming resins comprising copolymers of vinylidene chloride andacrylonitrile are also known in the art, such being disclosed in Cooveret al. US. Patent No. 2,831,826. Preferred fiber-forming resins of thislatter type are mixtures comprising (A) 70% to by weight of a copolymerof from 30% to 65% by weight of vinylidene chloride and 70% to 35% byweight of acrylonitrile, and (B) 30% to 5% by weight of a second polymerconsisting of (1) a hom-opolymer of an N-alkyl acrylamide where thealkyl group contains 1 to 6 carbon atoms, or (2) a copolymer of anN-alkyl acrylamide and an N-alkyl methacrylamide wherein the alkyl groupcontains 1 to 6 carbon atoms, or (3) a copolymer consisting of at least50% by Weight of an N-alkyl acrylamide wherein the alkyl group contains1 to 6 carbon atoms and not more than 50% by weight of a polymerizablemonovinyl pyridine monomer. The second polymeric material added to thecopolymer of vinylidene chloride and acrylonitrile is added mainly toimprove the dyeing characteristics of the composition and typicallyincludes such materials as poly- N-isopropyl acrylamides, a copolymer ofN-isopropyl acrylamide and 2-methyl-5-vinyl pyridine, a copolymer ofN-tert. butyl acrylamide and 2-methyl-5-vinyl pyridine, a copolymer ofN-isopropyl acrylamide and N-methyl methacrylamide, or related polymericmaterials. The

preparation of such mixtures is described in detail in theaforementioned Coover et al. patent.

The microbicide employed in the synthetic fibers and fabrics of theinvention, 3,4,4-trichlorocarbanilide, can be readily prepared byrefluxing equal molar proportions of 3,4-dichloroaniline and4-chloropheny1 isocyanate in an inert solvent such as diethyl ether.This microbicide is incorporated into a solution or dope or melt of theresin and thereafter spun by conventional methods into textile fibers tocontain about .05 to 5%, and preferably .2% to 2%, by weight of themicrobicide based on the weight of the synthetic fiber. The microbicideis substantially uniformly distributed in the fiber. Such fibers canthereafter be woven into fabrics, or they can be combined with otherfibers, natural or synthetic, and woven into fabrics. These fibers andfabrics have substantial microbicidal activity against suchmicroorganisms as Micrococcus pyogenes var. aureus, M icrococcusepidermidis, M icrococcus pyogenes, Diplococcus pneumoniae,Corynebacterium, diphtherialc, Streptococcus viridans, Lactobacilluscasei, and related microorganisms. The synthetic fibers and fabrics ofthe invention show particular microbicidal activity toward gram positivemicroorganisms. However, while the fibers and fabrics of the inventionhave microbicidal activity, they are substantially non-toxic andnon-irritating to humans and thus can be used in clothing, blankets,carpeting, and for numerous other uses.

A particularly desirable property of the present fibers and fabrics isthe permanence of the 3,4,4-trichlorocarbanilide distributed therein.Even in view of the substantial surface area of fabrics prepared fromthe present synthetic fibers, these fabrics can be subjected to morethan washings in household washing machines in the usual manner andstill exhibit microbicidal activity. Likewise, this microbicidalactivity can not be lost by mechanical abrasion of the fibers or thefabrics of the invention such as normally results in the processing anduse thereof. This permanence of microbicidal activity is attributed tothe incorporation of the 3,4,4-trichlorocarbanilide in the dope or meltof the resin before spinning into fibers as distinguished from coatingthe finished fabric with a microbicidal material.

The addition of 3,4,4-trichlorocarbanilide in the abovedefined amountsdoes not adversely alfect the physical properties of the fibers andfabrics of the invention such as strength, elongation, hand and luster.In addition, this microbicide is compatible in the fibers and fabrics ofthe invention as it does not oil out and does not cause discoloratingthereof under usual processing and usage. Also, this microbicide createsno difficulty in the sp nning of the fiber or in the dyeing of the fiberor fabric.

The invention is further illustrated by the following examples ofpreferred embodiments thereof.

Example 1 A cellulose acetate dope in acetone containing 28.5% by weightof cellulose acetate having an acetyl content of about 39% was prepared.To the dope was added 1% by weight of 3,4,4'-trichlorocarbanilide basedon the weight of the cellulose acetate. The resulting mixture wasblended and thereafter spun from the acetone into 55 denier, l3 filamentfibers. The resulting fibers containing about 1% by weight of3,4,4'-trichlorocarban1l1de substantially uniformly distributed thereinwere then woven into a fabric in the usual manner. The prepared fabricshowed inhibition against Micrococcus pyogenes var. aureus after 25launderings in the usual manner n a conventional household washingmachine. This inhlbition was determined by placing samples of the fabricin a petri dish containing nutrient agar surface inoculated with themicroorganism, a clear zone being formed around the test samples. Theprepared fabric has similar permanence of microbicidal resistance to Micrococcus epidermidis, Micrococcus pyogenes, Diplococcus pneumoniae,Corynebacterium diphtheriae and Streptococcus viria'ans. Similar resultswere obtained with fabrics prepared from cellulose acetate fiberscontaining 0.3% and 1.5% by weight of 3,4,4-trichlorocarbanilide. Thedescribed cellulose acetate fabrics containing the3,4,4-trichlorocarbanilide did not differ noticeably in dyeability, handand physical appearance from comparable cellulose acetate fabricscontaining no 3,4,4'-trichlorocarbanilide.

Example 2 A copolymer prepared from about 50% by weight of vinylidenechloride and 50% by weight of acrylonitrile was prepared in accordancewith the method described in Example 1 of Coover et al. U.S. Patent No.2,831,826 and thereafter dissolved in about four times its weight ofdimethyl :formamide. Then sufiicient 3,4,4'-trichlorocarbanilide waadded to the resulting dope which was spun into fibers as described inExample 1 above to produce fibers having about 1% by weight of the3,4,4-trichlorocarbanilide substantially uniformly distributed therein.Fabrics prepared from the resulting fibers have permanence ofmicrobicidal activity after more than 25 washings as described inExample 1 above. The described microbicidal fabric does not differnoticeably in dyeability, hand and physical appearance from comparablefabrics containing no 3,4,4'-trichlorocarbanilide.

Example 3 Several fiber-forming mixtures of polymers prepared inaccordance with the method of Coover et a1. U.S. Patent No. 2,831,826,were spun from acetone and woven into fabrics as described in Example 1above. With 1% by weight of 3,4,4'-trichl0rocarbanilide substantiallyuniformly dispersed in the prepared fiber-forming polymers, the fabricsprepared therefrom have substantial microbicidal activity. The preparedfibers had the following compositions: (a) a mixture of by weight of acopolymer of 52% by weight of acrylonitrile and 48% vinylidene chloride,and 15% by weight of poly-N-isopropyl acrylamide; (b) a mixture of 70%by weight of a copolymer of 50% by weight of acrylonitrile and 50% byweight of vinylidene chloride, and 30% by weight of a copolymer of byweight of N-tert. butyl acrylamide and 10% by weight of 2-methyl-5-vinylpyridine; (c) a mixture of 90% by weight of a copolymer of 50% by weightof acrylonitrile and 50% by weight of vinylidene chloride, and 10% byweight of a copolymer of N-isopropyl acrylamide and 2-methyl-5-vinylpyridine; and, (d) a mixture of 70% by weight of a copolymer of 50% byweight of acrylonitrile and 50% by weight of vinylidene chloride, and30% by weight of a copolymer of 90% by weight of N-isopropyl acrylamideand 10% by weight of N-methyl methacrylamide. Fabrics prepared fromthese fibers show permanence of microbicidal activity when tested asdescribed in Example 1 above. The described synthetic fabrics do notdiffer noticeably in dyeability, hand and physical appearance fromcomparable fabrics containing no 3,4,4-trichlorocarbanilide.

Example 4 A polyester of 1,4-cyclohexanedimethanol and terephthalic acidwas prepared by reacting 1,4-cyclohexanedimethanol (70% trans, 30% cis)and dimethyl terephthalate in accordance with the method described inExample 1 of copending Kibler et al. application, U. S. Serial No.554,639, filed December 22, 1955. By drawing a melt of the resultingpolymer containing 1% by weight of 3,4,4-trichlorocarbanilide intofibers, and spinning the fibers into a fabric, a fabric results that hassubstantial microbicidal activity. Such a fabric has permanence ofmicrobicidal activity after more than 25 washings as described niExample 1 above. The described microbicidal fabric does not differnoticeably in dyeability, hand and physical appearance from comparablefabrics containing no 3,4,4'-trichlorocarbanilide.

The microbicide of the invention can be prepared by the method describedin Example 5 below.

Example 5 To a suitable reaction vessel equipped with a thermometer,agitator and reflux condenser and containing 8.1 parts by Weight of3,4-dichloroaniline in 57 parts by Weight of diethyl ether is addeddropwise a solution of 7.7 parts by weight of 4-chlorophenyl isocyanatein 15 parts by weight of diethyl ether at such a rate as to maintaingentle reflux. Upon completion of the isocyanate addition the reactionmass is agitated for about one hour. The mass is filtered and theresidue washed with diethyl ether. The resulting3;,4,4'-trichlorocarbanilide product can be further purified byrecrystallization from ethanol.

The present invention thus provides novel synthetic textile fibers andfabrics which have considerable utility because of their built in orlocked in microbicidal activity, this microbicidal activity having apermanence in the present fibers and fabrics not possessed byconventional surface treated fibers and fabrics. in addition the 3,4,4-trichlorocarbanilide additive of the invention does not adversely affectthe processing, physical appearance and physical properties of thesubject fibers and fabrics.

Although the invention has been described in detail with reference tocertain preferred embodiments thereof, it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention as described hereinabove and as defined in the appendedclaims.

We claim:

1. A synthetic textile fiber having microbicidal activity havingsubstantially uniformly dispersed therein .05 to 5% by Weight of3,4,4'-trichlorocarbaniiide, said fiber comprising a resin from thegroup consisting of:

(I) cellulose acetate having an acetyl content of about (II) a polyestercomprised principally of the recurring structural unit (III) a mixtureof (A) 70% to 95% by weight of a copolymer of 30% to 65 by weight ofvinylidene chloride and 70% to 35% by weight of acrylonitrile, and

(B) 30% to 5% by weight of a second polymer from the group consisting of(1) a homopolymer of N-alkyl acrylamide wherein the alkyl group contains1 to 6 carbon atoms,

(2) a copolymer of N-alkyl acrylamide and N-alkyl methacrylamide whereinthe alkyl group contains 1 to 6 carbon atoms, and

(3) a copolymer consisting of at least 50% by weight of an N-alkylacrylamide wherein the alkyl group contains 1 to 6 carbon atoms and notmore than 50% by weight of a polymerizable monovinyl pyridine monomer.

2. A synthetic textile fiber having microbicidal activity comprisingcellulose acetate having an acetyl content of about 38% to 45% with .2%to 2% by weight of 3,4,4- trichlorocarbanilide substantially uniformlydistributed therein.

3. A synthetic textile fiber having microbicidal activity comprisingcellulose acetate having an acetyl content of about 38% to 41% with .2%to 2% by weight of 3,4,4- trichlorocarbanilide substantially uniformlydispersed therein.

4. A synthetic textile fiber having microbicidal activity comprising amixture of (A) 70% to 95% by Weight of a copolymer of from 30% to 65 byweight of vinylidene chloride and 70% to 35% by weight of acrylonitrile,and (B) 30% to 5% by weight of a second polymer from the groupconsisting of (l) a homopolymer of an N- alkyl acrylamide wherein thealkyl group contains 1 to 6 carbon atoms, (2) a copolymer of an N-alkylacrylamide and N-alkyl methacrylamide wherein in the alkyl groupcontains 1 to 6 carbon atoms, and (3) a copolymer consisting of at least50% by weight of an N-alkyl acrylamide wherein the alkyl group contains1 to 6 carbon atoms and not more than 50% by weight of a polymerizablemonovinyl pyridine monomer, with .2% to 2% by weight of3,4,4--trichlorocarbani1ide substantially uniformly distributed therein.

5. A synthetic textile fiber having microbicidal activity comprising amixture of (A) 70% to by weight of a copolymer of from 30% to 65% byweight of vinylidene chloride and 70% to 35% by weight of acrylonitrile,and (B) 30% to 5% by Weight of poly-N-isopropylacrylamide, with .2% to2% by Weight of 3,4,4'-trichlorocarbanilide substantially uniformlydistributed therein.

6. A synthetic textile fiber having microbicidal activity comprising amixture of (A) 70% to 95 by weight of a copolymer of from 30% to 65% byweight of vinylidene chloride and 70% to 35 by weight of acrylonitrile,and (B) 30% to 5% by weight of a copolymer of N-isopropyl acrylamide and2-methyl-5-viny1 pyridine, with .2% to 2% by weight of3,4,4-trichlorocarbanilide substantially uniformly distributed therein.

7. A synthetic textile fiber having microbicidal activity comprising amixture of (A) 70% to 95 by weight of a copolymer of from 30% to 65 byweight of vinylidene chloride and 70% to 35% by weight of acrylonitrile,and (B) 30% to 5% by weight of a copolymer consisting of at least 50% byweight of N-isopropyl acrylamide and not more than 50% by weight ofN-methyl methacrylamide, with .2% to 2% by weight of3,4,4-trichlorocarbanilide substantially uniformly distributed therein.

8. A synthetic textile fiber having microbicidal activity comprising amixture of (A) 70% to 95 by weight of a copolymer of from 30% to 65 byweight of vinylidene chloride and 70% to 35 by Weight of acrylonitrile,and (B) 30% to 5% by weight of a copolymer of N-tert. butyl acrylamideand 2-methyl-5-vinyl pyridine, with .2% to 2% by weight of3,4,4'-trichlorocarbanilide substan tially uniformly distributedtherein.

9. A synthetic textile fiber having microbicidal activity comprising apolyester of 1,4-cyclohexanedimethanol and terephthalic acid having therecurring structural unit with .2% to 2% by weight of3,4,4'-trichlorocarbanilide substantially uniformly dispersed therein.

10. A fabric having microbiological activity comprising fibers asdefined in claim 1.

References Cited in the file of this patent UNITED STATES PATENTS2,695,858 Lisle Nov. 30, 1954 2,758,955 Johnson Aug. 14, 1956 2,774,708Cohen Dec. 18, 1956 2,812,332 Pennino Nov. 5, 1957 2,846,398 Beaver eta] Aug, 5, 1958 2,913,369 Haslam Nov. 17, 1959- FOREIGN PATENTS 627,710Great Britain Aug. 15, 1949 684,404 Great Britain Dec. 17, 1952 709,982Great Britain June 2, 1954 UNITED STATES PATENT OFFICE CERTIFICATION OFCORRECTION Patent No- 3,034,957 May 15, 1962 James L. Smith et a1.

id Letters Patent should read as corrected below.

Column 4, line 70 for "ni" read in column 5 lines 39 to 42, the fa rmulashould appear as shown below instead of as in the patent:

CH2CH2 /CH=CH 0 -0CH2 CH' cH-c1l1 -0 -c -c\ c-c- \CH2CH2 \CH-CH/ Signedand sealed this 16th day of October- 1962.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents

1. A SYNTHETIC TEXTILE FIBER HAVING MICROBICDAL ACTIVITY HAVINGSUBSTANTIALLY UNIFORMLY DISPERSED THEREIN .05% TO 5% BY WEIGHT OF3,4,4''TRICHLOROCARBANILIDE, SAID FIBER COMPRISING A RESIN FROM THEGROUP CONSISTING OF: (I) CELLULOSE ACETATE HAVING AN ACETYL CONTENT OFABOUT 38% TO 45% (II) A POLYESTER COMPRISED PRINCIPALLY OF THE RECURRINGSTRUCTURAL UNIT